Soluble starch.



UNITED STATES PATENT oriuon.v

ALBERT EH11 MTLITZ, OF LEVERKUSEN, NEAR FARBENFA'BRIKEN VORM. FRIEDR. BAYER 80 00., 0F ELIBERFELD, GERMANY, A COR- PORATION 0F GERMANY.

COLOGNE, GERMANY, ASSIGNOR T0 SOLUBLE STARGH.

No Drawing.

To all whom it may concern:

Be it known that I, ALBERT EMIL'MILITZ, chemist, citizen of the German Empire, re-

siding at Leverkusen, near Cologne, Gerthermore to be carried out at a higher temperature, as dilute acids 6. g. a 12 per cent. hydrochloric acid react u on starch at ordinary temperature only incompletely, and very slowly. Acetic acid does not react at all on starch at ordinary temperature.

have now found that a new soluble starch which excels all other sorts in quality can easily be prepared by treating a cold suspension of starch in acetic acid with small quantities of mineral acids 6. g. nitric acid, hydrochloric acid, sulfuric acid etc. The surprising eifect of the mineral acid is probably due to catalytic action. The solu ble starch thus produced being most probably an acetyl derivative of starch dissolves completely in hot-water to a limpid liquid which can be kept for a long time without.

coagulating as do the known soluble starch preparations. The product is an excellently adhesive substance which can be used as substitute for gum arabic, tragacanth, as

a thickening or finishing agent, etc.

In carrying out the new process practically I can proceed as follows, the parts being by weight; 500 parts of potato-flour are quickly introduced with continuous stirring into a mixture of 250 parts of a '98-99 per cent. acetic acid with 7% parts of nitric acid (40 .B.). The product of the reactlon, at first a rather thin liquid solidifies after a short time to an easily triturable solid. The mixture is allowed to stand for about 24 hours, then cold water is added and the new product is filtered off, washed with cold Specification of Letters Patent.

, Patented Nov. 23, 1909.

Application filed January 29, 1908. Serial No. 413,284.

water and dried at about 40 C. It looks like starch. It is a white amorphous powder, insoluble in cold water, but soluble in Water of about70 C. In, such a solution containing about 10 to 15% it furnishes a gluelike, strongly adhesive solution, which can be kept for weeks without losing its adhesive properties. This solution does neither eongeal no; coagulate. A solution of about 5% of the acetylated starch gives with iodin a violet color. After heating on the water bath a solution of about 10% of the new acetylated starch with caustic alkali, for

example with 0.5 gr. Na O to 10 gr. acetylated starch, starch cannot be recovered from this solution, nor can the formation of starch be observed during any stageof the reaction. After saponification with caustic alkali and distillation under the addition of phosphoric acid, acetic acid is obtained in the distillate. Of course other kinds or qualities of starch and other mineral acids may be employed.

I do not confine myself to the particulars given in the above example, which are merely typical and can be varied within wide limits without altering thereby the nature of this invention.

Having now described my invention and in what manner the same is to be performed, I declare that what I claim is The new acetylatedstarch obtained from starch and acetic acid, which is a white, amorphous powder, insoluble in cold water, but dissolving in hot water to a limpid, adhesive li uid, which can be kept for weeks without losing its adhesive properties, insoluble in hot or cold acetic acid glacial, giving with iodin solution a violet color, and which is not reconverted into the ori inal starch by the action of alkali,.-substant1ally as hereinbefore described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing I wltnesies.

ALBERT EMIL MILITZ. '[L. s.] Witnesses: O'rro Komo,

WM- WASHINGTON Bmmswrox. 

